Starting device for gas-engines.



G. B. PBTSCHE. STARTING DEVICE FORGAS ENGINES.

APPLICATION FILED P3125, 1907. i

Patented May 2, 1911;

2 SHEETSSHE'ET 1.

- D. v i

154 ATTORNEY.

Ill/$1? G. B. PETS CHE. STARTING DBVIGE FOB GAS ENGINES.

APPLICATION FILED FEB. 25, 1907, 99 1,233. Patented May 2, 1911.

2 SHBETS-SHEET 2.

A I i G G E, X I. I

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i .1 6' I G l WITIIESSES: may/non MA/ JJJ s r/ares "earns Won.

GUSTAV BERNHARD PETSGHE, OF PHILADELPHIA, PENNSYLV'ANIA, ASSIGNOR 1'0SOUTHWARK FOUNDRY AND MACHINE COIKPANY, OF PHILADELPHIi, PENNSYL- VANIA,A CORPORA'IIGN 0F PENNSYLVANEA.

STARTING- DEVICE FOR GAS-ENGINES.

Specification of Letters Patent.

Patented May 2,1911.

Application filed. February 25, 1907. Serial No. 359,291.

To all whom it may concern: 1

Be it known that I, GUs'rAv B. Parsons, a subject of the Emperor ofGermany, residing in the'city. and county of Philadelphia, in the Stateof Pennsylvania, have invented a certain new and useful Improvement inStarting Devices for Gas-Engines, of which the following is a true andexact descrip tion, reference being hadto the accompany" ing drawings,which form a part thereof. My present invention relates to the startingof gas engines'by compressed air or gas and is primarilyflesigned. foruse in starting gas engines having four explosive chambers, in each ofwhich the operation is-on the four cycle plan, and as so designed, mypresent nvention comprises mechanism actuated by the valve gearcontrolling the valves of the engine in normal operation. The startingmechanism thus actuated by the regular valve gear in starting admitscompressed air or gas to each explosive chamber or working cylinder end,during the portionof thev cycle carried out in said chamber or cylinderend correspondingto the stroke of the piston therein which in regularoperation would be the working stroke.

Thus considered, my present invention diili'ers from that described andclaimed by my prior application, Serial Number 238,918, filedDecember-30, 190%, in important features of construction and arrangementof the starting mechanism and the manner in which it is actuated by theregular valve gear, the object of my present invention be ing tosimplify and improve upon the invert.

tion of my prior application.

While primarily dcsig ied for use with gas engine of the characterreferred to fllIlOVE, my invention comprises numerous novel features ofconstruction and arrangement not necessarily limited to'use with anyparticular typeof engine.

The various features of novelty which.

characterize my invention are pointed out with particularity 111 theclaims annexed to and formlng a part of this specification.

For a better understanding of my invention,

however, and rife advantages obtained there by, reference may be had tothe accompany ing drawings and descriptive matter in which 1 haveillustrated somewhat diagra 'nmatically, one of the torms in which myinvention may be carried out.

Inth drawings, Figure 1 .is a semi-diagrammatic figure, showing myimproved starting mechanism applied to gas engines having two doubleacting cylinders arranged in tandem. Fig. 2 is a transverse sectionalelevation through one of the working cylinders, showing the regularinlet and outlet valves and actuating mechanism therefor, and also thestarting valve mechanism. Fig. 3 is a sectional elevation of the pilotstarting valve, and Fig. 4 is a sectional plan of the main startingvalve taken on the line iit of Fig.2.

Referring to the drawings, A, A represent the working cylinders arrangedin tandern, the pistons A in the cylinders (not shown in Fig. 1) beingconnected to each other by the piston rod C 0*, C and C represent theregular exhaust valve casings at the ends of the cylinders, each of thevalve oasings'being connected by exhaust pipes D to the main ex haustpipe D the main outlet or exhaust valve E, one in each of the casings (3G and C and inlet valve mechanism l? for each cylinder 7 end areoperated in any suitable manner so that the operation in each cylinderis carried out on the four cycle plan. In the engine shown the regularvalve actuating mechanism is arranged so that the stems E E E andconnected to the exhaust valves in the casings C, C C and Crespectively, open successively in regular order, and of course each onepiston stroke before the opening of the corresponding inlet valve FL lnthe form disclosed in Fig. 2 the four main inlet valves F, and the fourmain exhaust valves E are operated by two sets of cams G and G \hichreciprocate in paths parallel to the cylinders A, A and are operated bycranks set ninety degrees apart on a shaft, rotating at half the speedof the main driving shaft of the engine. I have inlet passage orchamber, H and an'outlet passage or chamber, H The inlet chamber H ofeach valve'is connected by a port H to the pipe H The pipes H areconnected in turn to the supply pipe H which is the 5 source ofcompressed air, and by the term compressed air I mean to include anyfluid under pressure of thegeneralcharacter of compressed air.Similarly, each exhaust chamber H9 is connected by a port H to the 10corresponding exhaust pipe H, which may be open to the atmosphere or maybe connected into the main exhaust pipe D Ports H and HF lead from theadmission and exhaust chambers H and H respectively, to

15 the centrally located piston valve chamber H A passage H leads fromoneend of the chamber H to the passage 0 connecting the correspondingcylinder end with the main exhaust port 0, controlled by thecorresponding main exhaust valve E. It should be noted that the diameterof each valve E is less than the width of the corresponding ipassage CIn consequence, the valves E, :which extend into the passages C do notfill the latter and do permit-air to pass to any combustionchainberifro'm the corresponding startingvalve port H when thecorresponding valve E is on itsseat.

In ndrmal operation the'passages H and C areseparated by the valve 1,the stem'I of which carries the piston I working in the chamber H of thestarting valve casing. Ont-he item Iis slidingly mounted-the largepiston 'working in the chamber H. A spring J, surrounding the stem 1extends between the pistons I and I and normally holds them in thepositionshown in Fig. a in which they are fully separated and the valveI is on its seat. I The piston '1 has con- 40 nected to it a guidingextension I which works in the chamber H and also the hollow pistonvalve I", which moves from the position-shown in Fig. 4 in which itcloses the ports H to the position in which it opens these ports andcloses the ports H The inlet chambers L of the pilot valves L aresupplied withcompressed' air when the starting mechanism is inoperation, in any suitable manner as by connecting them through smallpipes K to theports H leading from'the inlet chambers of the variousstarting valves. The outlet chamber L of each pilot valve is connectedby'a pipe M to the port H leading to the inner end of the chamber H inwhich the piston I of the proper starting v lve works, The chambers Land L of each pilot valve, are normally separated bya piston valve Lworking in e a cylinder L open\ at itslower end to the valve chamber Land having its interior connected with the valve chamber L by a seriesof ports L". The stemgL of each pilot valve is adapted to engage an armE carried by the stem of'the corresponding 55 main (exhaustQvalve, andto he held by said arm when the main exhaust valve is closed in theposition shown in Fig. 3, in which the piston 1s below the ports L andthe chambers L and L are separated. When the arm E is raised, however,as the main exhaust valve opens, the piston L is moved by the airpressure beneath it to a position above the ports L? and communicationis thus established between the chambers L andL. (See left hand end ofFig. 1). The arrangement is such that the pipe M from each pilot valveruns to the starting valve of the cylinder end in which in normaloperation a working stroke would be carried outwhile the exhaust valvecontrolling the pilot valve is open. The inlet chamber H of eachstarting valve is connected'by a passa e H and pipe H, to the outerouter end 0 the chamber H in which the piston I works.

Instarting the gas supply admitted to the cylinders by the valves F, inregular operation is cut ofi, and the pipes H are supplied I withcompressed air or gas by the supply pipe H, The pressure of thecompressed air thus admitted to the inlet chambers H and transmittedtherefrom through the ports H and pipe H to the outer ends of thevarious chambers H is suiiicient to move the pistons I to the rightagainst the action of the springs J, and thus move all the valves I oiltheir seats, whereby each cylinder end is in communication through thepassage C with the passage H.

In any position in which the engine may have stopped one of the mamexhaust valves E is left open and the corresponding stem raised. (InFig. 1 the extreme left end stem I E is raised.) In consequence thecorresponding piston valve L is moved by the air pressure in the chamberL to connect the chambers L and L and pressure passes to the port H ofthe proper starting valve casing; via, the casing H when the parts arein the position shown in Fig. 1. This pressure acting on the inner sideof the large piston I moves it to the left against the action of thespring J, and closes the ports H bf that starting valve and opens theports H admitting compressed air to the corresponding cylinder end fromthe inlet chamber H of the starting valve casing which chamber is incommunication with the compressed air supply pipe H through pipe H Thespring J is not sufliciently strong to move the piston I outward againstthe action of the pressure acting on it, so that the valve I remainsopen. The pressure thus admitted to the cylinder end starts the enginein operation and at the end of a piston stroke the main exhaustvalvevwhich was open, is closed by the regular valve gear, whereupon thecorresponding pilot valve is of course closed and the starting valvecontrolled by it returns to its original condition, a leadage portorports L being provided to permit the escape of air from the pilotvalve chamber L Wlien starting valve returns to its original osition thepiston I closes ports H and opens ports H thus allowing the air in thecorresponding end of the working cylindento escape through ports H intothe starting valve outlet chamber H and from thence into the outlet pipeH As one main exhaust valve closes another opens thus allowing the pilotvalve controlled by it to open and the operation thus described, isrepeated to admit pressure to. another cylinder end and so 0 By the useof my invention the piping for supplying compressed air to the cylinderends to move the engine is simple-and can be conveniently disposed, amatter of considerable importance, especially in large engines, whereproper disposition of the ordinary starting devices is a troublesomematter. The pipes K and M connected to the pilot valves can be, ofcourse, much smaller than the main pipes supplying the compressed air,and -a suitable disposition of these smaller pipes is easily obtained.

The starting mechanism can be applied in a very simple manner to theregular valve gear without necessitating any change in the operation orconstruction of the latter, e xcept theaddition of the arms E orequivagl'ent devices. While I prefer to operate the starting valves fromthe stems of the .ex-

haust valves as shown, it will. of course be understood that they may beoperated from.

other portions of the valve gear, or indeed, under some circumstances,it may be desirable to operate them from some other moving parts of theengine. It will, of course, be understood that certain features of myinvention may be employed without a corresponding use of others.

. Usually in two or three revolutions of the engine shaft sufficientmomentum is acquired by the fiy-wheel to carry the engine along and thestarting mechanism is then cut out of service by the simple expedient ofcutting off the supply of compressed air, and at the same time theregular supply of explosive mixture is connected to the engine, whichthen operates in the regular manner. Having now described my invention,what desire to secure by Letters Patent is: Y

1. In a gas engine having one or more working chambers and a valve gearcontrolling the admission to and exhaust from each chamber in normaloperation, starting'mechanism including a starting valve casing for eachchamber having a passage leading to the corresponding working chamberand another passage. and means for supplying compressed air to the lastmentioned passage, a valve in said casing controlling communication.between said passages, and fluid pressure actuating means for saidvalve, including a pilot controlling valve, means,actuated by the valvegear for controlling said pilot valve and a pipe controlled by saidpilot valve and running from the pilot valve to the starting valvecasing.

2. In a gas engine having a plurality of working chambers, startingvalve casings,

ings, a starting valve in each starting valve casing and fluid pressureactuating mechanism for the starting valves including a pilot valve foreach starting valve adjacent to-and operated by a moving part of theengine. p

3. In a gas engine having a plurality of working chambers, a mainexhaust valve casing for each chamber, said main exhaust valve casingsbeing arranged side by side, starting valve casings one attached to eachmain exhaust valve casing, pipes for supplying compressed air to the.starting valve casings, one connected to eachv starting valve casing,starting valves, one in each starting valve casing and fluid pressureactuating mechanism for the starting valves, including a pilot valve foreach starting valve located adjacent to and operated by a moving part ofthe engine.

4. In a four-cycle gas engine having one or more Working chambers and avalve gear for controlling the admission to and exhaust from eachchamber in normal operation, starting mechanism comprising a startingvalve for each chamber operating in starting to admit compressed ,air tosaid chamher during the piston stroke which in normal operation would bethe working stroke, and to connect the chamber to exhaust during theother piston. stroke, means for supplying each starting valve withcompressed air and means for operating said valves including a pilotvalve for. each starting valve and connections from the pilot valves tosaid valve gear.

5. In a' four-cycle gas engine having one or more working chambers and avalvegear for controlling the admission to and exhaust from each chamberin regular operation, starting mechanism including a starting valvecasing for each, chamber having a supply passage or chamber and anexhaust chamber or passage connected to exhaust, means for supplyingcompressed air to said supply passage or chamber, a starting valve foreach casing movable from a position in which it closes communicationbetween the Working chamber and the exhaust passage to a position inwhich it .closes communication between the Working chamber and thesupply passage, and means controlled by the valve gear for movingeach ofsaid startingvalves so that each working chamber is connected to thesupply passage during the period corresponding to the working stroke,carried out in the chamber in regular operation and to exhaust at othertimes.

6. In a four-cycle gas engine having one or more working. chambers,starting mechanism including a valve casing for each working chamberhaving a passage leading to said chamber, a supply chamber, and anexhaust chamber connected to exhaust, and having the supply and exhaustchambers connected to said passage by inlet and exhaust portsrespectively, means for supplying said supply chamber with compressedair, a valve located in said'passage for controlling the inlet andexhaust ports, and

means for moving said valve in starting to open said lnlet port duringthe piston stroke which inlnormal operation would be the working strokeand to open the exhaust port during the strokes which in normal operation would be the exhaust, admission and compression strokes.

7. In a four-cycle gas engine having one or more working chambers,starting mecha nism lncluding starting valve casings, one for eachcombustion chamber, each of said casings having a passage leading to theworking chamber, a supply chamber and an exhaust chamber connected toexhaust, and having said supply and exhaust chambers connected to saidpassage by ports, means for'supplying compressed air to said supplychamber, a valve controlling said ports and movable from a position inwhich it opens one port and closes the other to a position in which itcloses the one and opens the other, yielding means tending to hold thevalve at all times in one of said positions, and means actuated by themovement of the enginefor moving the valve at intervals into the otherposition.

8. In a gas engine having a plurality of working chambers, and a valvegear for controlling the admission to and exhaust from said chambers inregular operation, starting mechanism including a valve casing for eachworking chamber, said casing having a passage connected to the workingchamber, a

supply chamber connected to said passage by an inlet port, an exhaustchamber connected to exhaust and to said passage by 'an exhaust port,and a piston chamber, means for supplying compressed air to said supplychamber, a valve controlling said ports and movable from a position inwhich it closes the inlet port and opens the exhaust port to a positionin which it closes the exhaust port and opens the inlet port, yieldingmeans tending to hold the valve in one position, and means for movingthe valve against the action of said yielding means to the otherposition, said means including. a piston, a pilot valve controllingcommunication between ,said piston chamber and said source of compressedair and a connection from said valve gear for controlling said pilotvalve.

In a gas engine having a plurality of working chambers, startingmechanism'ineluding starting valve casings one for each chamber, eachstarting valve casing having a valve chamber 11, inlet and exhaustchambers H and H" connected to the .valve chamber by the ports H and Ilrespectively, and also having the piston chambers II and H meanssupplying one end of ""tl1e latter chamber in starting with fluid underpressure, a starting valve mechanism for each starting. valve casing,including a valve I controlling communication between the valve. chamberand the corresponding working chamber, piston I connected to the valveI, working in chamber H and arranged to open the valve'I when'thepressure is admitted to said end of the chamber H piston I working inchamber H valve I connected to piston I and controlling ports H and Hand a spring J, normally holding piston I in position in which valve Icloses port H and uncovers port H and means actuated by the movements ofthe engine for intermittently admitting fluid under pressure to chamberH to move the valve I? through piston I? to uncover port H and closeport H 10. In a gas engine having a plurality out working chambers,starting mechanism including starting valve casings one for eachchamber, each starting valve casing having a valve chamber H ,inlet andexhaust chambers H and H connected to the valve chamber by the ports Hand 1-1 respectively, and also having the piston chambers H and H meanssupplying one end of the latter chamber in startin with fluid underpressure, a starting valve mechanism for each starting valve casing,including a valve I controlling communication between the valve chamberandthe corresponding working chamb" r, piston I connected to the valve Iand working in chamber H and arranged to open the valve I when pressureis admitted to said end of the chamber H piston I working in chamber Hvalve I connected to piston I and controlling ports H and H and aspring. J tending to hold pistons I and I in the positions in which thevalve I is closed and the port H is covered and the-port H isuncovered,. and means actuated by the movements of the engine forintermittently admitting fluid under pressure to chamber H to move thevalve I through piston I to uncover port H and close port H 11. In a gasengine having a plurality of working chambers, starting mechanism including starting valve casings one for each chamber, each starting valvecasing having under pressure, a starting valve mechanism for eachstarting valve casing, including a valve I cont-rolling communicationbetween the valve chamber and the corresponding working chamber, pistonI connected to the valve 1 and workingin chamber H and arranged toopen'the valve I when pressure is admitted to said end of the chamber Ipiston I working in chamber H ,,valve I connected to piston I andcontrolling ports H and H and a spring J, normally holding piston I inposition in which valve 1 closes port H and uncovers port H pilot valvesL, one for each starting valve, each pilot valve having an inlet chambersupplied with fluid under pressure and an outlet chamber connected tothe end of the chamber H, from which the piston 1 moves to uncover theport and cover the port H and means supplied by the movement of theengine for intermittently actuating saidpilot valves to connect theirinlet and outlet sides.

12. Ina gas engine having a pluralityof Working chambers a valve gearcontrolling the admission to and exhaust from the working chambers innormal operation, a starting valve for each Working chamber, fluidpressure actuating mechanism therefor, including a pilot valve for eachstarting-valve, each pilot valve comprising a casing having an inletchamber supplied with fluid under pressure, an outlet chamber connectedto the starting valve and a valve member movable from a position inwhich communication between the inlet and outlet chambers is closed to aposition in which communication between 'said chambers is establishedand a connection between said valve cham ber and-the valve gear wherebythe latter moves said valve member from one of said positions to theother.

13. In a gas engine having a plurality of working chambers and a valvegear for controlling the admission to and exhaust from said chambers inregular operation, a starting valve for each chamber and fluid pressureactuating mechanism therefor, including a pilot valve for each startingvalve, said pilot valve having a casing with an inlet chamber suppliedwith fluid under pressure, and an outlet chamber, said chambers beingconnected by a passage, and a valve member controlling said passage andnormally urged from the position. in which communicationbetween thechambers is closed to the position in which it is open by the fluidpressure in the inlet chamber, and a connection from said valve gearwhich normally holds said valve member in the position in which thepassage is closed but in termittently allows the valve member to move toopen said passage.

14. In an internal combustion engine having inlet and outlet valves andmeans for operating them, a starting v'alve, a compressed air supply,mechanism operated by compressed air for opening the starting valve andkeeping-it open, and independent means for regulating the admissionandexi haust of compressed air through the start ing valve. GUSTAV BERNHAEDPETSCHE- Witnesses: I

ARNOLD KATZ, JOHN E. HUBBELL.

